Passage 8.25.13
οὐ γὰρ ἄν ποτε οὐδὲ νηὶ παρισουμένας πορθμίδι παράσχοιτο ὁ Λάδων νήσους. κάλλους μὲν γὰρ ἕνεκα οὐδενὸς ποταμῶν δεύτερος οὔτε τῶν βαρβαρικῶν ἐστιν οὔτε Ἕλληνος, μέγεθος δὲ οὐ τοσοῦτος ὡς ἐν αὐτῷ καὶ νήσους ἀναφαίνεσθαι καθάπερ ἐν Ἴστρῳ τε καὶ Ἠριδανῷ.
For the Ladon would never offer islands that could rival even a ferry-boat in size. Indeed, in beauty it is second to none of the rivers, neither among the barbarian nor among the Greek; yet it is not large enough for islands to appear in it, as they do in both the Ister and the Eridanos.